Antenna Distance to Fixed Axle
Contents
1. Leica MOJORTK ee Auto steer with Virtual Wrench Mua HOW TO GUIDE Antenna Distance to Fixed Axle This document describes how to set the Antenna Distance to Fixed Axle in the Leica mojoRTK system This setting is now part of the vehicle setup wizard and needs to be understood for improved performance of the system The intended audience of this document includes Leica Geosystems approved resellers and internal support personnel Description The Antenna Distance to Fixed Axle is a relatively new setting that needs to be entered into the system Correctly setting this offset in the Leica mojoRTK console improves line acquisition and on line performance of the auto steering sub system Note that the Antenna Distance to Fixed Axle should not be confused with the Antenna Fore Aft setting in the Leica mojoRTK Vehicle Settings menu The Antenna Distance to Fixed Axle is to aid the positioning system in the Leica mojoRTK to provide an accurate speed and direction The Antenna Fore Aft setting is used to help the steering control system and is explained separately in Appendix A Benefits Correctly setting the Antenna Distance to Fixed Axle improves the system s calculation of the vehicle speed and direction This in turn improves steering performance of steering systems supported by the Leica mojoRTK system Although some steering systems will only show moderate improvements other steering systems will experience greatly improved perf2. com G t Page 8 9 Document 1065 rev1 2 eosysiems Leica MOJORTK amp Auto steer with Virtual Wrench yua Appendix B Glossary Antenna Fore Aft The Antenna Fore Aft setting is used to move the control point see below of the vehicle along the front to rear center line of the vehicle If the control point is in front of the antenna the Antenna Fore Aft setting is positive if the control point is behind the antenna then the Antenna Fore Aft setting will be negative Control Point This is mentioned in Appendix A Antenna Fore Aft and is a point along the vehicle s front to rear center line It is this point which the steering control system is trying to get onto the working line The position of the control point is dependant on the antenna position and the Antenna Fore Aft setting Fixed Axle The fixed axle is the non steering axle In a front wheel assist or front wheel steer this is the rear axle on a rear wheel steer it is the front axle On an articulated tractor it should be considered that the front axle is the fixed axle On a tracked machine it should be considered to be the line between the front to rear center of the left track to the front to rear center of the right track See diagrams in Table 1 Antenna Distance to Fixed Axle The antenna distance to fixed axle is the distance along the center line of the vehicle between the GPS antenna and the fixed axle see fixed axle definition above If the GPS antenna i
3. these instructions below begin to apply vapo Determining the Value to Enter As the Antenna Distance to Fixed Axle Once you have made your way to the Ant Dist to Fixed Axle section of the Vehicle Wizard you need to know how to figure out what value it is that you need to enter into the system The Antenna Distance to Fixed Axle is the distance along the center line of the vehicle between the red GPS antenna and the non steering axle of the vehicle for an articulated tractor the front axle is used There is one other thing to be careful of Depending on the type of vehicle the antenna distance to fixed axle may be positive or negative and it is very important to get this right Table 1 below shows diagrams of various vehicles and explains the how the offset should be worked out for each one NOTE in all these diagrams the antenna is shown on the center line of the vehicle but with the Leica mojoRTK system the antenna will be off to one side The measurement will be the same if it is made from the antenna to the center line of the fixed axle For more information when it has to be right CLCa www AgGuidance com Page 2 9 Document 1065 revl 2 Geosystems Leica MOJORTK x Auto steer with Virtual Wrench Mua NOTE in all diagrams refer to measurement number 1 for the antenna distance to fixed axle NOTE when entering the offset in US Standard or Imperial units the value is entered in inches with quarter inc
4. at steer the vehicle It helps the vehicle react a little earlier when straightening onto the line during line acquisition NOTE Where possible the Antenna Fore Aft setting should be left at zero However if it is found that a non zero setting is required it should be kept as low as possible as there are negative effects on system performance as the Antenna Fore Aft setting gets larger Refer to Diagram A1 below Note that the mojoRTK system has the red and black antennas to each side but for the purpose of explaining the Antenna Fore Aft we will assume that we only have one antenna mounted in the middle This is essentially what the Red Antenna Offset in the mojoRTK Vehicle Wizard does The diagram is being used to show two scenarios regarding the Antenna Fore Aft setting e Scenario 1 no Antenna Fore Aft setting Antenna Fore Aft set to Zero e Scenario 2 Antenna Fore Aft setting adjusted to put the control point over the middle of the front axle When the mojoRTK system is attempting to steer the vehicle onto the line it uses a point on the vehicle called the control point It is the control point that the system is trying to steer onto the line For Scenario 1 with the Antenna Fore Aft set to zero the control point will be right where the antenna is shown on the diagram In this case the control point is not on the line so the control system will continue drive the vehicle towards the right to try and get the control poin
5. behind this line and so the Antenna Distance to Fixed Axle is negative Examples 1 01m 39 75 For more information www AgGuidance com Page 5 9 Document 1065 revl 2 Leica MOJORTK amp Auto steer with Virtual Wrench Mua when it has to be right Seica Geosystems Leica MOJORTK x Auto steer with Virtual Wrench Mua 5 Self Propelled Sprayer In this case it doesn t matter if the boom is at the front or the rear of the vehicle as long as in both cases the non steering axle is the rear axle NOTE this is not the case for a Hagie all wheel steer sprayer In the case shown the antenna is in front of the fixed axle so the fixed axle offset will be positive Examples 9 22M 205 5 k For more information when it has to be right eca www AgGuidance com G t Page 6 9 Document 1065 rev1 2 ecosystems Leica MOJORTK amp Auto steer with Virtual Wrench Mua Appendix A The Antenna Fore Aft Setting The Antenna Fore Aft setting should not be confused with the Antenna Distance to Fixed Axle as they perform quite different functions The Antenna Distance to Fixed Axle assists the mojoRTK positioning system to provide a more accurate heading and velocity where as the Antenna Fore Aft setting assists the steering control system to acquire and hold the line The Antenna Fore Aft setting can help steering systems which are only capable of slowly turning the wheels th
6. h resolution k For more information when it has to be right CLCa www AgGuidance com G Page 3 9 Document 1065 rev1 2 eosystems Leica MOJORTK amp Auto steer with Virtual Wrench yua Table 1 Examples of antenna distance to fixed axle values for various vehicle types In all cases distance number 1 in the diagrams is the Ant Dist to Fixed Axle 1 Front Wheel Steer In this case the antenna is in front of the fixed axle and therefore the Antenna Distance to Fixed Axle is positive Examples 1 01m 39 75 2 Combine Harvester In the case shown here the antenna is in front of the fixed axle so the fixed antenna axle offset is positive Examples 0 46m 18 0 NOTE if the antenna is behind the fixed axle unlike what is shown here the offset will be negative Ll il Bend Pod feed Peed bl bl ll Pend Decl Bend Peel Peed Poul bl feud Peel Peel Deel eel Peel eel k For more information when it has to be right CLCa www AgGuidance com G Page 4 9 Document 1065 revl 2 eosystems 3 Articulated Tractor With an articulated tractor both axles are fixed and for proper control the front axle is used for the offset However the antenna Is behind the front axle so the Antenna Distance to Fixed Axle is negative Examples 1 36m 53 5 4 Tracked Tractor Use the line between the front to rear center of the tracks as the line of the axle The GPS antenna is usually
7. ormance Limitations Although all steering systems supported by the Leica mojoRTK system will benefit from correctly setting the Antenna Distance to Fixed Axle some systems will not be improved as much as others Required ltems Leica mojoRTK system installed into a vehicle with a supported steering platform k For more information when it has to be right CLCa www AgGuidance com G Page 1 9 Document 1065 rev1 2 eosystems Leica MOJORTK amp Auto steer with Virtual Wrench yua Instructions To set the Antenna Distance to Fixed Axle you will need to get into the Vehicle Wizard in the mojoRTK console There are two ways to do this 1 If the console is new or has just been reset to factory defaults the console will start up in the initial setup wizard and the vehicle wizard is a sub set of the set up wizard In this case progress through the setup wizard as per the Leica mojoRTK user manual until you get to the Ant Dist to Fixed Axle section where the instructions below begin to apply OR 2 You can get into the vehicle wizard from the menus in the Leica mojoRTK console The steps are a From the main navigation screen of the Leica mojoRTK console press OK to get into the main menu Select Settings and press OK Select Vehicle and press OK Select Vehicle Wizard and press OK Go through the vehicle wizard as per the Leica mojoRTK user manual until you get to the Ant Dist to Fixed Axle section where
8. s in front of the fixed axle the offset will be positive if the antenna is behind the fixed axle the offset will be negative k For more information when it has to be right CLCa www AgGuidance com G Page 9 9 Document 1065 revl1 2 eosystems
9. t onto the line For Scenario 2 with the Antenna Fore Aft set to put the control point over the middle of the front axle the control point is considered to be on the line though it is obviously going to go past the line In reality the control system will have straightened the vehicle to the line before getting into this situation however the diagram was drawn to demonstrate the difference between the two control points k For more information when it has to be right CLCa www AgGuidance com G Page 7 9 Document 1065 rev1 2 eosystems Leica MOJORTK amp Auto steer with Virtual Wrench weoual lf the control point is in front of the antenna then the Antenna Fore Aft setting will be set to a positive number If the control point is behind the antenna then the Antenna Fore Aft setting will be negative this may be the case on a self propelled sprayer for example For Scenario 2 the Antenna Fore Aft will be set to the distance shown by measurement 1 in the diagram and will be positive because the control point is in front of the antenna To set the Antenna Fore Aft setting go into the main menu of the mojoRTK system then go to Settings Vehicle Antenna fore aft Diagram A1 Antenna Fore Aft and Control Point NOTE the mojoRTK system has the antennas to each side but for now consider the antenna to be in the middle Working Line k For more information when it has to be right CLCa www AgGuidance
Download Pdf Manuals
Related Search